Both Tremain and Goodhew won what were safe Labour seats in 2005. Napier had been with Labour for decades, and Chris Tremain has made it an incredibly safe seat for himself. It helped to have Russel Fairbrother as the opponent, but Tremain is hugely high profile and popular in Napier.
Likewise Goodhew won Aoraki off Jim Sutton in 2005, turning a 6,500 deficit into a 6,500 margin, and she increased that to 8,000 on teh new Rangitata boundaries.
Both will be Ministers sooner rather than later – possibly even in this term if Key does a reshuffle before the election.